AFDPHI AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 758 PM EDT WED MAY 11 2011 .SYNOPSIS... A RIDGE OF HIGH PRESSURE ACROSS THE REGION THIS EVENING WILL REMAIN THROUGH THURSDAY AND THEN WEAKEN AND MOVE EAST. LOW PRESSURE WILL ADVANCE FROM THE GREAT LAKES AND OHIO VALLEY AND ARRIVE OVER OUR AREA THIS WEEKEND. A FRONTAL SYSTEM AHEAD OF THE LOW WILL BRING SHOWERY WEATHER THIS WEEKEND AND INTO NEXT WEEK. && .NEAR TERM /THROUGH THURSDAY/... NOT MUCH IN THE WAY OF CHANGE TO THE FORECAST FOR THE OVERNIGHT. IT LOOKS LIKE THE MAIN MASS OF LOW CLOUDS ASSOCIATED WITH THE SURFACE LOW WELL EAST OF THE COAST WILL BYPASS SOUTHEAST AREAS TONIGHT. THERE IS A LINE OF STRATOCUMULUS TRAPPED UNDER THE INVERSION EXTENDING FROM SOUTHWEST NEW ENGLAND THROUGH THE CENTRAL NEW JERSEY COAST. A RECENT AMDAR SOUNDING FROM KLGA SHOWS THE TOP OF THE MIXED LATER NEAR 5600 FEET. NEAR TERM GUIDANCE SHOWS THIS MOISTURE REMAINING TRAPPED UNDER THE INVERSION FOR THE REST OF THE EVENING...SO THE CLOUDINESS FOR THE NEW JERSEY SHORE WAS INCREASED TO ACCOUNT FOR THE UPSTREAM STRATOCUMULUS. ELSEWHERE...ANY LOCAL CUMULUS OR STRATOCUMULUS SHOULD DISSIPATE DURING THE NEXT COUPLE OF HOURS...WITH SKIES BECOMING MOSTLY CLEAR THEREAFTER. MOST OF THE CIRRUS FROM THE CONVECTION BACK OVER THE UPPER MIDWEST AND GREAT LAKES SHOULD THIN AS IT RIDGES THE MID LEVEL RIDGE POSITION...AND DROP SOUTHEAST ACROSS THE EASTERN OHIO VALLEY AND WESTERN NEW YORK STATE AND PENNSYLVANIA. THIS SHOULD HAVE NO TANGIBLE EFFECT ON SKY COVER TONIGHT. TEMPERATURES APPEAR TO BE ON TRACK. THE LATEST LAMP GUIDANCE SUGGESTS THAT LOWS APPEAR TO BE WITHIN REACH IN MOST PLACES. WITH DEW POINTS MAINLY IN THE 40S...NOT EXPECTING TO MAKE MANY CHANGES TO THE OVERNIGHT LOWS. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... THE WEATHER HAS BEEN GREAT THE PAST FEW DAYS...AND THURSDAY AND MOST OF FRIDAY SHOULD REMAIN THE SAME...BUT CHANGES TO A MORE UNSETTLED AND WET PATTERN WILL BEGIN DURING THE END OF THE SHORT TERM. THE HIGH THE HAS PROVIDED THE NICE WEATHER WILL DRIFT OVER THE AREA THURSDAY AND THEN WEAKEN WHILE PASSING OFF THE COAST FRIDAY. THIS WILL ALLOW LOW PRESSURE AND ITS ASSOCIATED FRONTS TO ADVANCE INTO THE ERN PART OF THE COUNTRY. WE WILL KEEP THE FCST DRY THROUGH FRIDAY BUT THEN THE OPERATIONAL MODELS AND THE MOS BEGIN TO INDICATE THAT SHOWERS WILL BE ARRIVING. A SLGT CHC FOR SHOWERS WAS KEPT IN FOR FRI NIGHT WITH A SMALL CHC FOR SHOWERS SAT. A FEW TSTMS MAY ARRIVE SAT AFTERNOON... SO I WILL LEAVE THOSE IN THERE FROM THE PREVIOUS FCST. TEMPERATURES WILL NOT BE EXCESSIVELY WARM WITH PREVAILING WINDS REMAINING FROM AN ONSHORE DIRECTION. HIGH TEMPERATURES THURSDAY WILL MOSTLY BE IN THE 70S...NEAR 70 ON FRIDAY AND MOSTLY IN THE 60S SATURDAY. READINGS NEAR THE SHORE WILL PROBABLY BE 5 TO 10 DEGREES COOLER. LOWS WILL MOSTLY BE IN THE 50S. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AN H5 TROF AND SEVERAL AREAS OF LOW PRESSURE WILL DOMINATE THE EXTENDED PD. SO EXPECT A CLOUDY AND UNSETTLED WX PATN. WHILE NO DAY WILL BE A COMPLETE WASH OUT, BUT THERE WILL BE PERIODS OF SHOWERS. MODELS DIFFER ON TIMING OF THE FEATURES THAT WILL MOVE THROUGH, AND THEREFORE ITS DIFFICULT TO PINPOINT THE RAINIEST PERIODS, BUT STILL IT DOESN`T LOOK TO BE THE NICEST WEEKEND AND CERTAINLY NOT AS NICE AS LAST WEEKEND. WENT AT OR SLIGHTLY BELOW GUID TEMPS THIS WEEKEND DUE TO CLOUD COVER AND RNFL POTENTIAL, BUT STILL TEMPS SHOULD BE AROUND NRML THRU THE PD. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... VFR CONDITIONS ARE FORECAST FOR MOST OF THE TAF PERIOD. SOME CUMULUS/STRATOCUMULUS CLOUDS DEVELOPED EARLY IN THE DAY AND MAY LINGER OVERNIGHT. IT LOOKS LIKE WE MIGHT DEVELOP SOME MVFR CIGS THURSDAY MORNING, BUT IF THEY DO DEVELOP, THEY SHOULD LIFT DURING THE DAY AS THE AIR WARMS AND MIXING DEPTH INCREASES. THE NAM MOS WAS STILL GIVING RDG SOME MVFR FOG AROUND DAYBREAK, SO WE KEPT IT IN FOR NOW. WINDS HAVE BEEN RATHER LIGHT EXCEPT FOR A FEW GUSTS DURING THE DAY, THEREFORE EVEN THOUGH THE SYNOPTIC FLOW SHOULD BE FROM THE NORTHEAST, WE HAVE HAD SOME VARYING WINDS AT TIMES TODAY. ANY DIRECTION EARLY MAY BECOME MORE EASTERLY OR EVEN SOUTHEASTERLY, THEN REMAIN VARIABLE OVERNIGHT AND INTO THE EARLY PART OF THURSDAY, BEFORE INCREASING OUT OF THE EAST TO SOUTHEAST DURING THE DAY. OUTLOOK... FRIDAY SHOULD BE ANOTHER FAIRLY NICE DAY, ALTHOUGH CLOUDS ARE EXPECTED TO INCREASE LATE IN THE DAY. THE WEEKEND INTO EARLY NEXT WE WE ARE EXPECTED TO SEE LOWERING CIGS AND VSBYS LIKELY WITH RAIN AT TIMES. IF WE BECOME UNSTABLE ENOUGH, WE MAY EVEN EXPERIENCE SOME THUNDERSTORMS AT TIMES AS WELL. WINDS THROUGH THE PERIOD ARE STILL EXPECTED TO REMAIN OUT OF THE EAST TO SOUTHEAST FOR MUCH OF THE TIME. && .MARINE... WINDS HAVE HAD A HARD TIME GUSTING TODAY AND ARE NOT LIKELY TO BE VERY WINDY OVER THE NEXT FEW DAYS AS HIGH PRESSURE REMAINS ACROSS THE AREA. HOWEVER, WITH A PERSISTENT NORTHEAST TO EAST FLOW, SEAS ARE EXPECTED TO REMAIN ELEVATED OVER THE NEXT FEW DAYS. THEREFORE WE HAVE CHANGED THE SMALL CRAFT ADVISORY TO SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS. SEAS SHOULD REMAIN 4 TO 7 FEET ALONG THE COASTAL WATERS. NO ADVISORY IS EXPECTED FOR THE DELAWARE BAY AT THIS TIME AS WINDS ARE EXPECTED TO REMAIN BELOW CRITERIA LEVELS. WINDS MAY BEGIN TO INCREASE LATE SATURDAY INTO EARLY NEXT WEEK AS AN AREA OF LOW PRESSURE APPROACHES THE WATERS FROM THE WEST AND THE PRESSURE GRADIENT TIGHTENS. SMALL CRAFT ADVISORIES WILL LIKELY BE NEEDED AGAIN, BUT WE WILL NEED TO MONITOR THE FORECAST IN CASE GALES ARE NEEDED. && .TIDES/COASTAL FLOODING... THE COASTAL FLOOD ADVISORY HAS BEEN TAKEN DOWN FOR THE EASTERN SHORE OF MARYLAND. CAMBRIDGE DID REACH THE MINOR TIDAL FLOODING LEVEL, BUT TOLCHESTER FELL SHORT. WE ARE NOT CONFIDENT ON THE NEXT TIDE CYCLE EITHER, SO FOR NOW WE WILL ISSUE A COASTAL FLOOD STATEMENT STATING THAT WE MAY APPROACH MINOR TIDAL FLOODING OVER THE NEXT FEW TIDE CYCLES DUE TO THE PERSISTENT NORTHEAST FLOW NOT ALLOWING WATER TO EVACUATE THE BAY. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT FRIDAY FOR ANZ450>455. && $$